There is a demand for a zoom lens, of which a total lens length (a distance from a first lens surface to the image plane) is short and a size of the zoom lens is small and which has high optical performance in the entire zoom range with a high zoom ratio, as an optical image pickup system used in an image pickup apparatus. Further, there is also a demand for a zoom lens having means for correcting image blur.
Patent Literature 1 discloses a zoom lens that performs image blur correction by integrally rotating a plurality of lens systems, which move along loci different from one another during zooming, about a barycentric position or a position in the vicinity of the barycentric position as a center. Further, Patent Literature 2 discloses an optical image pickup system in which an optical system for image blur correction including a first lens having a negative power and a second lens having a positive power is disposed on an object side of a main lens system. During image blur correction, at least one of the first lens and the second lens rotates.
Generally, for a zoom lens having an image stabilization function, there is a demand to accurately execute image blur correction, and there is a demand to have less fluctuation in aberrations at the time of image blur correction. In order to satisfy such demands, it is important to appropriately set a lens configuration of a zoom lens, a lens configuration of an image stabilization lens system for image blur correction, and the like. Unless the lens configuration of the image stabilization lens system moving for image blur correction is appropriate, image blur correction is insufficient, and an amount of occurrence of decentering aberration increases at the time of image stabilization. As a result, it is difficult to keep optical performance excellent at the time of image stabilization.
In the photography lens having an image blur correction function of Patent Literature 1, a plurality of lens units is integrally rotated. Hence, a degree of freedom of correction in the decentering aberration, which is caused at the time of image blur correction, is restricted. Hence, it is difficult to keep optical performance favorable at the time of image blur correction.
Further, in the zoom lens of Patent Literature 2, by rotating at least one of the first lens and the second lens, image blur correction is performed. In Patent Literature 2, an image blur correction system is mounted on a front surface of a main lens system. Hence, a size of the entire optical system tends to increase.